One of the engineers I worked with at Vicinity is an avid Ham Radio Operator and has created an interesting site for N1RZ Six Meter Path Data tracking. I can only pretend to fully understand what's going on here, but since it is map based I think it's cool (and there's FAQs to learn more).
It's great to find new and surprising hobbies on the internet. I bought MS Flight Sim a while back and during the process of trying to find an updated driver I ran across a whole parallel avaition universe where flight sim pilots, and air traffic controllers (they can simulate anything), go to work at night flying "real" routes and logging "real" flight time in the pursuit of higher and higher rank (and simulated pay) in a totally simulated airline. Here's some of the links:
And of course you can really improve upon your simulation environment!
And for the hardcore math-aviators out there here is a great collection of Aviation Formulary from Ed Williams.